摘要:

The influence exerted by radiant flux on transient thermal degradation of PMMA and particle board has been investigated. The mass loss rate has been measured continuously during experiments performed on specimens of dimensions equal to 10 x 10 cm in the range 1-4 W/cm2. The effects of oxygen content of the gaseous atmosphere surrounding the material have also been studied by comparing results obtained in air and in nitrogen. Dependence of the mass loss rale on the temperature of the gases has been briefly investigated as well.

ISSN:0010-2202    

DOI:10.1080/00102208408923722

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A new technique, based on sideward scattering, is presented for evaluating the modal drop size in non-absorbing liquid sprays.

ISSN:0010-2202    

DOI:10.1080/00102208408923723

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Velocity and concentration measurements were taken using specially fabricated probes for the initial region of a concentric air jet containing sand particles in the secondary stream. Similarity of velocity and concentration distributions is observed in the annular shear layers. A theoretical model is developed to predict the entrainment and it is seen that particles enhance the mixing. This trend is confirmed by experimental results.

ISSN:0010-2202    

DOI:10.1080/00102208408923724

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Ignition characteristics of the pool surface of an O/W emulsified gelled hydrocarbon fuel with high internal phase ratio were investigated from the standpoint of spilled-fuel fire prevention. Flash points of miscellaneous gelled fuels with single and multiple components, and of commercial fuels were measured and compared with those of neat hydrocarbon fuels. The Tag Closed-Cup method was used for flash point measurement. A dispersive type infrared gas analyzer (DIR)was used to measure the temperature dependence of the equilibrium vapor concentration of the emulsified fuel. Ignition aspects of an emulsified fuel pool surface were studied and compared with those for neat liquid fuel, here a small hot Nichrome wire adjacent to the pool was used to heat the surface locally. The procedure was also recorded in a 16 mm movie and inter-ferogram form. It was found that whether the neat fuel is a single substance or a multi-component mixture has an effect aside from that of emulsification on the elevation of the flash point. The effect of emulsification on the elevation of flash point was analyzed in terms of the reduction of fuel vapor pressure due to solubilization in emulsion, Another finding is that by heating the surface locally the emulsified fuel pool can be easily ignited, due to the considerable reduction of heat loss from the hot region since there exists no internal convection flow, even when the initial temperature of the emulsion is quite low and the flash point of neat hydrocarbon fuel is higher than the ambient temperature.

ISSN:0010-2202    

DOI:10.1080/00102208408923725

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Flame spreading along the pool surface of O/W (oil-in-water) emulsion type gelled hydrocarbon fuels with high internal phase ratios have been investigated from the standpoint of spilled-fuel fire prevention. Aspects of flame spreading and temperature field in the vicinity of the spreading flame front were observed and measured by 16 mm movie pictures, interferometry and thermocouples. It was found that a thin liquid layer flow ahead of and below the flame exists if the neat hydrocarbon fuel has a flash point higher than the ambient temperature and or has considerably different flash and fire points. No such liquid layer flow can be observed if the neat fuel has a flash point below the ambient temperature and consists of a single component. Whether such a liquid layer flow exists or not would have a large influence on such aspects of flame spreading as velocity, direction and steadiness. The influences of the initial temperature and the oil content of O/W emulsion on flame spreading velocity were investigated. Characteristics of flame spreading upward and downward along an inclined pool were also examined by altering the inclination angle and comparing results with those for a horizontal pool.

ISSN:0010-2202    

DOI:10.1080/00102208408923726

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The problem of low-frequency instability in ramjet dump combustors is examined. An instability model is presented which asserts that a coupling occurs between two processes, one located in the combustion zone and the other at the choked nozzle. Pressure disturbances are produced as entropy waves convect through tlie nozzle, and entropy waves are generated as the pressure disturbances perturb the combustion zone. An approximate linearized stability theory is developed for the case of near blow-off (which corresponds to maximum rumble ). Both oscillation frequencies and amplification rates are obtained.

ISSN:0010-2202    

DOI:10.1080/00102208408923727

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor